• Food Science of Animal Resources
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• v.27 no.1
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• pp.127-131
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• 2007

In order to investigate the presence of pathogenic bacteria in fresh pig loin and the growth changes of microorganism in raw ham during storage at 10 and $25^{\circ}C$. These hams were manufactured according to a short-ripening procedure being completed in 4 weeks with dry-curing followed by wet-curing and ripening. The result regarding the contamination level of microorganism in the fresh raw pig loin showed that the count of total aerobes was $3.11\;log\;CFU/cm^2$, and the population of lactic acid bacteria, Pseudomonas spp., Clostridium spp., and yeast and mould had not risen over $2\;log\;CFU/cm^2$ on the storage time. However, the average count ofEnterobacteriaceae in pork loin was $3.11\;log\;CFU/cm^2$, which represented the predominant species. The pathogenic bacteria including Salmonella spp, Staphylococcus aureus, Vibrio parahaemolyticus, Clostridium perfringene, Listeria monocytogenes, and Escherichia coli O157:H7 were not detected either in fresh pork loin or in raw ham products stored at 10 and $25^{\circ}C$. The initial count of total aerobes in raw ham samples was 3.06 log CFU/g, and increased slightly after 90 days at 10 and $25^{\circ}C$ to 4.6 and 4.69 log CFU/g, respectively. The predominant species in raw ham products during storage time were lactic acid bacteria and Staphylococcus spp.

• Journal of the Korean Ceramic Society
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• v.53 no.3
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• pp.354-361
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• 2016

The purpose of this study was to prepare lightweight foamed concrete by mixing coal fly ash of circulating fluidized bed combustion(CFBC) with cement, and to develop uses for recycling by analyzing carbonation behavior resulting from a change in conditions for pressurized carbonation. For concrete, CFBC coal fly ash was mixed with Portland cement to the water-binder ratio of 0.5, and aging was applied at room temperature after 3 days of curing at $20^{\circ}C$, RH 60%. For carbonation, temperature was fixed at $60^{\circ}C$ and time at 1 h in the use of autoclave. Pressures were controlled to be $5kgf/cm^2$ and the supercritical condition of $80kgf/cm^2$, and gas compositions were employed as $CO_2$ 100% and $CO_2$ 15%+N2 85%. In the characteristics of produced lightweight concrete, the characteristics of lightweight foamed concrete resulting from carbonation reaction were affirmed through rate of weight change, carbonation depth test, air permeability, and processing analysis for the day 28 specimen. Based on these results, it is concluded that the present approach could provide a viable method for mass production of eco-friendly lightweight foamed concrete from CFBC coal fly ash stabilized by carbonation.

• Environmental Engineering Research
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• v.12 no.3
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• pp.101-108
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• 2007

Fixation of lead contaminants in the solidification/stabilization using Portland cement has been investigated by X-ray diffraction, scanning electron microscopy and compressive strength. The presence of lead was observed to produce lead carbonate sulfate hydroxide ($Pb_4SO_4(CO_3)_2(OH)_2$), lead carbonate hydroxide hydrate ($3PbCO_3{\cdot}2Pb(OH)_2{\cdot}H_2O$) and two other unidentified lead salts in cavity areas and was observed to significantly retard the hydration of cement. By 28 days, howevere, the XRD peaks of most of the lead precipitates have essentially disappeared with only residual traces of lead carbonate sulfate hydroxide and lead carbonate hydroxide hydrate evident. After 28 days of curing, hydration appears well advanced with a strong portlandite peak present though C-S-H gel peaks are not particularly evident. Lead species produced with the dissolution of lead precipitates are fixed into the cement matrix to be calcium lead silicate hydrate (C-Pb-S-H) during cement-based solidification.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.66.2-66.2
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• 2015

There is the urgent need of new human health care's technology against cancers or tumors based on plasma electronics, medicine and biology. Main target of our study is to enhance efficacy and selectivity of plasma on cancer cells with metabolic modifiers and by inducing immune-modulations. We have evaluated the combination effect of plasma with metabolic modifiers (2-DG) on various solid and liquid cancers. Our findings suggest that 2-DG enhances the efficacy and selectivity of plasma and induces apoptosis in blood cancer cells through glucose deprivation. Finally, we conclude that 2-DG with non-thermal plasma may be used as a combination treatment against cancer cells. Our work also comprises plasma induced activation of immune cells; which find applications for curing various kinds of resistant tumors and other dreadful diseases. Plasma significantly activates immune cells which increases cell death in solid tumors in co-culture conditions.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.3
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• pp.554-563
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• 1999

For the purpose of elucidating the polymerization modes of dual-cure restorative materials and comparing them with single-cure restorative materials, a study was performed on the light-cured composite resin, dual-cure composite resin, dual-cure glass ionomer cement and chemical-cure glass ionomer cement. By measuring the microhardness of each material at 0mm, 1mm and 3mm depth during initial 24 hours with predetermined interval, the state of polymerization and degree of conversion was indirectly evaluated for each material, and obtained results are as follows : 1. All of four materials tested showed significant increase in microhardness after 24hrs compared with just after curing starts. 2. In all materials except Ketac-fil, there showed a significant difference in microhardness between each depth at each time interval. 3. In the test of lap time till final curing for each material, the polymerization process was revealed to last longer in the dual-cure type materials than in single-cure type materials at 3mm depth. Based on the results above, it was demonstrated with materials of dual-cure mode that the degree of conversion increases by successive curing reactions even in the deeper layers where sufficient curing light is impermeable.

• Korea Journal of Hospital Management
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• v.3 no.1
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• pp.134-164
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• 1998

The purpose of this study is to provide the data for the co-operative treatment of western and oriental hospital. The studies were made a questionnaire to analyze inpatients' awareness on the systems of co-operative treatment and to observe the differences in medical service satisfaction between inpatients who had experienced the co-operative treatment of western and oriental hospital(Group 1) and those who did not (Group 2). The survey was conducted in February 1998, on 250 inpatients who were in a hospital which provided co-operative treatment of western and oriental medicine in Pusan. Korea. The results of this study were disclosed as follows: 54.2% of western hospital inpatients and 90.5% of oriental hospital inpatients suffered from diseases of the nervous system 88.9% of Group 1 and 72.2% of Group 2 believed that the co-operative treatment of western and oriental hospital was more effective in curing diseases of the nervous system. 33.5% or inpatiens in the western hospital and 87.4% of inpatients in the oriental hospital had received the co-operative treatment. In the case of the oriental hospital inpatients who had experienced western treatment, 36.8% received an examination radiologic, 30.7% received a laboratory test, 17.8% received physical therapy, and 14.1% received medication. Whereas, in case of the western hospital inpatients who had experienced oriental treatment, 71.8% received acupuncture, 23.9% received herbal medicine, and 2.8% received oriental medical tests. As to the opinion on the systems of co-operative treatment, 49.6% of Group 1 agreed that 'New medical institutions that adopt the merits of both western and oriental medicine are absolutely necessary.', and 48.9% of Group 1 agreed that 'Since there are strong points and weak points in both western and oriental medicine, partial and gradual introduction of the two systems would be better.' Whereas, 49.6% of Group 2 agreed that the partial and gradual introduction, and 35.7% of Group 2 agreed that the necessity of the new medical institutions. As to the motives for visiting the hospital, the most popular reason for all the inpatients was "others' advice". In the case of Group 1, however, the most popular reason was "the possibility of co-operative treatment". In regards to medical cost, the oriental hospital inpatients felt that their medical cost was too expensive. On the other hand, a smaller percentage of the western hospital inpatients felt that western hospital medical cost were too expensive. And between Group 1 and Group 2, a higher percentage of Group 1 felt that their medical cost was too expensive.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.953-958
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• 2001

The concrete which has placed under cold weather has some defects such as the decrease of initial strength by hydration delay, strength unrecover at unhardened concrete freezing and structural failure and crack by expansion pressure. So, in this study, we tried to develope the concrete which can be made under cold weather without defect by using of do-icing agency In concrete test, the used do-icing agency has the characteristics of de-icing and rapid hydration. By test results, Co{$NH_{2}$$]_{2}$is unsuitable for workability, and NaN$O_{2}$ is the most suitable agency for cold weather. And for curing, the cured concrete at $21^{\circ}C$ for 24 hours has the safe strength.

• Proceedings of the KAIS Fall Conference
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• 2007.11a
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• pp.359-362
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• 2007

본 실험에서는 Polyimide (PI)의 전구체인 Poly(amic acid) (PAA)의 제조를 위하여 2,2-BIs(3,4-anhydrodicarboxyphenyl)hexafluoropane(6FDA)와 4-aminophenyl sulfone로 PAA를 합성하였다. 이를 열을 가하여 Polyimide가되는 반응을 적외선 분광법을 이용하여 추적하였다. 이미드화 반응은 $80^{\circ}C$에서 1시간, $120^{\circ}C$에서 1시간, $240^{\circ}C$에서 1시간, $250^{\circ}C$에서 1시간, 2경화시킴으로 완결됨을 확인하였다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.416-424
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• 2023

Concrete emits a large amount of carbon dioxide throughout its life cycle, and due to the societal demand for carbon dioxide reduction, research on storing carbon dioxide in concrete in the form of minerals is ongoing. In this study, cyanobacteria, which absorb carbon dioxide through photosynthesis and fix it as calcium carbonate, were applied to a porous concrete substrate, and the changes in the properties of the concrete substrate due to their special environmental curing condition were analyzed. The results showed that the calcium carbonate precipitation by the microorganisms was concentrated in the light-exposed surface area, and most of the precipitation occurred in the cement paste part, not in the aggregate. This microbially induced calcium carbonate precipitation enhanced the mechanical performance of the paste and improved the overall compressive strength as the curing age progressed. In addition, the increase in microbial biofilm and calcium carbonate improved the pore structure, which influenced the reduction in water permeability.

• Journal of the Korean Geotechnical Society
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• v.40 no.2
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• pp.19-28
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• 2024

This study explores the long-term decline in the uniaxial compressive strength of Controlled Low Strength Material (CLSM) by preparing a sample with a 1:1 mixing ratio of CLSM and water. Uniaxial compressive strength tests were conducted after 7 and 28 days of curing. The results revealed that the compressive strength at 28 days was reduced by a factor of 2.85 compared to that at 7 days. Additionally, when expansion was introduced under the same mixing conditions, there was a significant reduction in compressive strength. Point load strength tests based on 7 and 28 days of curing indicated a disparity of 29.27 to 58.76 and 48.19 to 95.13 times, respectively, between the point load strength and the uniaxial compressive strength at 7 days. The differences observed in the findings of this study compared to previous studies may be attributed to variations in the precision of the test method and the sample production process. Therefore, it is essential to establish clear testing methods to accurately evaluate CLSM.